The topic of this post is dear to my heart. My go-to for "very good sound" on the cheap is the Sony STR DA1000ES receiver. I recently purchased my third from ebay for $130 or so. This box is just so musical. Can't believe the bass coming out of my KEF aluminum "egg" speakers (3" woofers?). Great sound.
My Onkyo TX-SR876 HT receiver ($1400 in 2008) is my HT workhorse. You should see the power supply transformer in this baby! I think there is a cottage-industry looming for using these power supplies when the receiver dies. Would make a great two-channel amp. Would break my heart to just throw it away.